Our research involves the synthesis of a large variety of functional derivatives of C60 and C70 which have potential application as antiviral agents, particularly against HIV, and in photodynamic therapy as sensitizers of singlet oxygen. In the latter connection, we are synthesizing porphyrin-fullerene hybrids in which C60 and porphyrins are connected by various flexible and rigid spacer groups, exemplified respectively by polyether and steroid moieties. Mass spectral data are absolutely necessary for the characterization of such compounds, and thus a number of samples have been submitted for both FAB and ESI MS. In the latter connection, compounds are prepared containing a crown ether moiety which can be complexed with metal cations such as potassium prior to ESI mass spectral analysis.